Ca3Sc7(Si5Ir2)4

High-Entropy Materials HEA

MP-ID: mp-3293635 · Space group: Amm2 (#38)

Materials Project API

Basic Information

Formula

Ca3Sc7(Si5Ir2)4

MP-ID

mp-3293635

Elements

Sites

Density

6.5365

g/cm³

Volume

643.83

Å³

Cell a

12.4553

Cell b

12.4553

Cell c

4.1502

α Angle

90.00

β Angle

90.00

γ Angle

90.14

Space Group

Amm2

Point Group

mm2

Crystal System

Orthorhombic

Bravais Lattice

Stability

Yes

Packing Fraction

X-ray Diffraction

Diffraction Pattern

Target / Radiation

X-axis: 2θ (°); Y-axis: relative intensity; Cu Kα ; λ=1.5418 Å

Diffraction Peaks (Top 24)

2θ	d (Å)	I	hkl
10.03	8.8181	2.3	(1,-1,0)
10.06	8.7964	1.5	(1,1,0)
15.89	5.5757	6.6	(2,-1,0)
15.93	5.5647	6.1	(2,1,0)
20.14	4.4091	56.7	(2,-2,0)
20.19	4.3982	60.0	(2,2,0)
21.41	4.1502	63.4	(0,0,1)
25.76	3.4584	3.4	(3,-2,0)
25.82	3.4505	2.5	(3,2,0)
26.78	3.3292	2.5	(2,-1,1)
26.80	3.3268	2.2	(2,1,1)
28.67	3.1138	50.3	(4,0,0)
29.55	3.0226	3.2	(4,-1,0)
29.56	3.0220	45.1	(2,-2,1)
29.59	3.0191	2.8	(4,1,0)
29.59	3.0185	43.8	(2,2,1)
30.41	2.9394	2.0	(3,-3,0)
30.49	2.9321	2.1	(3,3,0)
31.30	2.8580	2.3	(3,-1,1)
31.32	2.8558	2.2	(3,1,1)
36.01	2.4940	1.5	(4,-3,0)
36.06	2.4907	100.0	(4,0,1)
36.10	2.4881	1.5	(4,3,0)
36.78	2.4438	5.2	(5,-1,0)

Get direct link

Energy Properties

Formation Energy/atom

-0.86890

eV/atom

Energy/atom

-19.16507

eV/atom

Energy above Hull

0.0000

eV/atom

Uncorrected Energy

-19.1651

eV/atom

Volume/atom

16.94

Å³

c/a Ratio

0.3332

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Total Mag. Moment

0.0048

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.000010

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Si · 0.526

Element Family

Metalloid-Nonmetal

Solute Fraction

0.474

Interstitial Fraction

0.526

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.1779

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

9.7932

J/mol·K

Ω Parameter

0.4700

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

18.185%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.3537

smaller = more stable mixing

VEC

4.711

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-39.316

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8497

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (1)

aaahfkgh

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-3293635

Reference Citation

The crystal structure and related material properties of Ca3Sc7(Si5Ir2)4 were obtained from the Materials Project database (MP-ID: mp-3293635, database version v2026.04.13).

Literature Citation

Horton, M.K., Huck, P., Yang, R.X. et al. Accelerated data-driven materials science with the Materials Project. Nat. Mater. 24, 1522–1532 (2025). https://doi.org/10.1038/s41563-025-02272-0

3D Crystal Structure Rendering

Loading 3D structure…

Style: Ball & Stick | Drag to rotate · Scroll to zoom · Right-click to pan

Raw CIF Data

# generated using pymatgen
data_Ca3Sc7(Si5Ir2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.45531358
_cell_length_b   12.45531358
_cell_length_c   4.15016700
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.14142997
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ca3Sc7(Si5Ir2)4
_chemical_formula_sum   'Ca3 Sc7 Si20 Ir8'
_cell_volume   643.83351777
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ca  Ca0  1  0.11537766  0.61523864  0.50000000  1.0
  Ca  Ca1  1  0.88476136  0.38462234  0.50000000  1.0
  Ca  Ca2  1  0.61486947  0.88513053  0.50000000  1.0
  Sc  Sc3  1  0.38266254  0.11733746  0.50000000  1.0
  Sc  Sc4  1  0.67144669  0.17182334  0.50000000  1.0
  Sc  Sc5  1  0.32817666  0.82855331  0.50000000  1.0
  Sc  Sc6  1  0.17571480  0.32428520  0.50000000  1.0
  Sc  Sc7  1  0.82622055  0.67377945  0.50000000  1.0
  Sc  Sc8  1  0.00114556  0.99975207  0.00000000  1.0
  Sc  Sc9  1  0.50024793  0.49885444  0.00000000  1.0
  Si  Si10  1  0.56664052  0.06724675  0.00000000  1.0
  Si  Si11  1  0.43275325  0.93335948  0.00000000  1.0
  Si  Si12  1  0.06892917  0.43107083  0.00000000  1.0
  Si  Si13  1  0.93161981  0.56838019  0.00000000  1.0
  Si  Si14  1  0.20275642  0.16438469  0.00000000  1.0
  Si  Si15  1  0.79840807  0.83553980  0.00000000  1.0
  Si  Si16  1  0.16605059  0.79997178  0.00000000  1.0
  Si  Si17  1  0.70002822  0.33394941  0.00000000  1.0
  Si  Si18  1  0.83442891  0.20223859  0.00000000  1.0
  Si  Si19  1  0.29776141  0.66557109  0.00000000  1.0
  Si  Si20  1  0.66446020  0.70159193  0.00000000  1.0
  Si  Si21  1  0.33561531  0.29724358  0.00000000  1.0
  Si  Si22  1  0.01328689  0.14983244  0.50000000  1.0
  Si  Si23  1  0.98644172  0.84983683  0.50000000  1.0
  Si  Si24  1  0.15481924  0.99813153  0.50000000  1.0
  Si  Si25  1  0.50186847  0.34518076  0.50000000  1.0
  Si  Si26  1  0.84902460  0.00708581  0.50000000  1.0
  Si  Si27  1  0.49291419  0.65097540  0.50000000  1.0
  Si  Si28  1  0.65016317  0.51355828  0.50000000  1.0
  Si  Si29  1  0.35016756  0.48671311  0.50000000  1.0
  Ir  Ir30  1  0.02274356  0.24153724  0.00000000  1.0
  Ir  Ir31  1  0.97840798  0.75855295  0.00000000  1.0
  Ir  Ir32  1  0.24596761  0.97953303  0.00000000  1.0
  Ir  Ir33  1  0.52046697  0.25403239  0.00000000  1.0
  Ir  Ir34  1  0.75736731  0.02362718  0.00000000  1.0
  Ir  Ir35  1  0.47637282  0.74263269  0.00000000  1.0
  Ir  Ir36  1  0.74144705  0.52159202  0.00000000  1.0
  Ir  Ir37  1  0.25846276  0.47725644  0.00000000  1.0

Get direct link